JP2009155602A - Ink for inkjet recording, ink cartridge and inkjet recording apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink for inkjet recording, the ink excellent in ejection stability and printing quality, preventing a compound derived from a rubber member or the like in an inkjet recording apparatus from being eluted into the ink, and excellent in toughness of a recording material. <P>SOLUTION: The ink for inkjet recording includes as essential components, a specific diazo compound; water; dipropylene glycol propyl ether (DPP); and a specific acetylene glycol surfactant, each component being blended in a specific percentage. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an ink for ink jet recording, an ink cartridge, and an ink jet recording apparatus.

  Conventionally, inks containing dyes, dipropylene glycol propyl ether, acetylene glycol surfactants, and the like are known as inks for inkjet recording (see, for example, Patent Document 1). The ink includes (1) excellent ejection stability even after long-term use, (2) excellent print quality, and (3) a compound derived from a material forming an ink jet recording apparatus. It is required to prevent elution into the ink, and (4) excellent fastness such as light resistance and ozone resistance of the recorded matter. However, none of the conventional inks satisfy all the above performances. Examples of the material forming the ink jet recording apparatus include a rubber member and an organic material member other than the rubber material. Examples of the rubber member include a wiper and a cap. For example, the wiper wipes the nozzle surface of the ink jet head. The cap blocks, for example, the nozzle surface and the outside world. When the compound derived from the rubber member or the like elutes into the ink, the compound may precipitate in the ink. When the compound is precipitated, for example, the nozzle of the inkjet head may be clogged.

Japanese Patent Laid-Open No. 9-111165

  Therefore, the present invention is excellent in jetting stability and printing quality, prevents elution of a compound derived from a rubber member or the like in an ink jet recording apparatus into the ink, and is excellent in fastness of recorded matter. The object is to provide ink.

前記一般式（１）において、
Ｒ_１は、水素原子、置換または無置換のアルキル基、置換または無置換のアリール基であり、
Ｒ_２は、水素原子、ハロゲン原子またはシアノ基であり、
Ｒ_３は、水素原子、置換または無置換のアルキル基、置換または無置換のアリール基、置換または無置換のヘテロ環基であり、
Ｒ_４、Ｒ_５、Ｒ_６およびＲ_７は、それぞれ、水素原子、置換または無置換のアルキル基、置換または無置換のアリール基、置換または無置換のヘテロ環基、置換または無置換のスルホニル基、置換または無置換のアシル基であり、Ｒ_４、Ｒ_５、Ｒ_６およびＲ_７は同一でも異なっていてもよいが、Ｒ_４とＲ_５が共に水素原子であることはなく、Ｒ_６とＲ_７が共に水素原子であることはなく、
Ａ_１およびＡ_２は、双方が置換または無置換の炭素原子であるか、若しくは一方が置換または無置換の炭素原子であり、且つ、他方が窒素原子である。

前記一般式（２）において、ｍおよびｎは同一でも異なっていてもよく、ｍ＋ｎ＝１〜１５を満たす数であり、
Ｒ_１１、Ｒ_１２、Ｒ_１３およびＲ_１４は、それぞれ同一でも異なっていてもよく、炭素原子数１〜５の直鎖状または分岐鎖状アルキル基である。 In order to achieve the above object, the inkjet recording ink of the present invention comprises:
An ink for ink jet recording comprising a colorant, water, a water-soluble organic solvent, and an acetylene glycol surfactant,
The colorant contains a dye represented by the following general formula (1),
The water-soluble organic solvent comprises dipropylene glycol propyl ether;
The acetylene glycol-based surfactant includes a surfactant represented by the following general formula (2),
The dye, the dipropylene glycol propyl ether, and the surfactant represented by the general formula (2) are blended so as to satisfy the following conditions (A) to (C), respectively. .

(A) 0.1 ≦ x ≦ 1.0
(B) 0.5 ≦ y ≦ 3
(C) In y ≧ 25x / 9 + 2/9,
−175x + 18y + 225z−104 ≦ 0 and
−100x + 18y + 225z−66.5 ≧ 0
In y ≦ 25x / 9 + 2/9,
−275x + 54y + 225z−112 ≦ 0 and
−200x + 54y + 225z−74.5 ≧ 0
x: blending amount (% by weight) of the dye with respect to the total amount of the ink
y: blending amount of dipropylene glycol propyl ether with respect to the total amount of ink (% by weight)
z: blending amount (wt%) of the surfactant represented by the general formula (2) with respect to the total amount of ink

In the general formula (1),
R ₁ is a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group,
R ₂ is a hydrogen atom, a halogen atom or a cyano group,
R ₃ is a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group,
R ₄ , R ₅ , R ₆ and R ₇ are each a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted sulfonyl group A substituted or unsubstituted acyl group, and R ₄ , R ₅ , R ₆ and R ₇ may be the same or different, but R ₄ and R ₅ are not both hydrogen atoms, and R ₆ and R ₇ is not both a hydrogen atom,
A ₁ and A ₂ are both substituted or unsubstituted carbon atoms, or one is a substituted or unsubstituted carbon atom and the other is a nitrogen atom.

In the general formula (2), m and n may be the same or different, and are numbers satisfying m + n = 1 to 15,
R ₁₁ , R ₁₂ , R ₁₃ and R ₁₄ may be the same or different, and are each a linear or branched alkyl group having 1 to 5 carbon atoms.

  As a result of a series of studies, the present inventors have found that the ink represented by the dye, the dipropylene glycol propyl ether, and the surfactant represented by the general formula (2) in the ink containing the dye (A) to When blended so as to satisfy the condition (C), the jetting stability and the printing quality are excellent, the elution of the compound derived from the rubber member or the like in the ink jet recording apparatus into the ink is prevented, and the recorded matter is robust. As a result, the present invention was found. Such an improvement in performance has been found for the first time by the present inventors. The mechanism by which the ink of the present invention is excellent in all of the above performances is assumed as follows, for example. The dye is excellent in fastness such as light resistance and ozone resistance of a recorded matter using an ink containing the dye. However, the ink containing the dye has a problem in ejection stability when used for a long period of time, for example. In contrast, the ink of the present invention is formulated so that the dipropylene glycol propyl ether and the surfactant represented by the general formula (2) satisfy the conditions (A) to (C). Even when used for a long period of time, the jetting stability is excellent, the printing quality is excellent, and further the elution of the compound derived from the rubber member or the like in the ink jet recording apparatus into the ink is prevented. These performance improvement mechanisms are speculations and do not limit the present invention. In addition, for example, in the case where a light color such as sky blue or skin color is expressed using ink with a large amount of colorant, it is necessary to reduce the dot density of the ink. The drop in the dot density causes a grainy feeling. On the other hand, the ink of the present invention has a small amount of the dye of 1.0% by weight or less, so that, for example, a light color can be expressed without reducing the dot density and no graininess is produced. . Thus, the ink of the present invention can be suitably used as, for example, a light ink with a small amount of colorant as described below.

  In the present invention, the light ink is, for example, an ink in which the blending amount of the colorant is 0.1 to 1.0% by weight relative to the total amount of the ink.

  In the ink for inkjet recording of the present invention, the amount of the dye (x), the amount of dipropylene glycol propyl ether (DPP) (y), and the surfactant represented by the general formula (2) with respect to the total amount of the ink The blending amount (z) is included in the space surrounded by the planes P1 to P8 of the xyz coordinate system shown in FIG.

  As described above, the inkjet recording ink of the present invention can be suitably used as, for example, a light ink. However, the present invention is not limited to this. The ink for ink jet recording of the present invention can be made into an ink other than the light ink (for example, a general dark ink) by using a colorant other than the dye.

  The use of the inkjet recording ink of the present invention is not particularly limited, and for example, it can be used as a magenta ink. However, the present invention is not limited to this. The ink for ink jet recording of the present invention can be made into ink of a color other than magenta by using a colorant other than the dye.

  The ink cartridge of the present invention is an ink cartridge containing ink for ink jet recording, and the ink is the ink for ink jet recording of the present invention.

  The ink jet recording apparatus of the present invention is an ink jet recording apparatus that includes an ink cartridge and an ink discharge means, and ink for ink jet recording is discharged from the ink discharge means, and the ink cartridge is the ink cartridge of the present invention. It is characterized by that.

  Next, the inkjet recording ink of the present invention will be described. The ink of the present invention contains a colorant, water, a water-soluble organic solvent, and an acetylene glycol surfactant. As described above, the colorant includes the dye.

  As described above, the dye is a dye represented by the general formula (1).

As described above, in the general formula (1),
R ₁ is a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group,
R ₂ is a hydrogen atom, a halogen atom or a cyano group,
R ₃ is a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group,
R ₄ , R ₅ , R ₆ and R ₇ are each a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted sulfonyl group A substituted or unsubstituted acyl group, and R ₄ , R ₅ , R ₆ and R ₇ may be the same or different, but R ₄ and R ₅ are not both hydrogen atoms, and R ₆ and R ₇ is not both a hydrogen atom,
A ₁ and A ₂ are both substituted or unsubstituted carbon atoms, or one is a substituted or unsubstituted carbon atom and the other is a nitrogen atom.

  In the general formula (1), examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

  In the general formula (1), the substituted or unsubstituted alkyl group is preferably an alkyl group having 1 to 6 carbon atoms. Examples of the substituted or unsubstituted alkyl group include a methyl group, ethyl group, n-butyl group, isopropyl group, tert-butyl group, hydroxyethyl group, methoxyethyl group, cyanoethyl group, trifluoromethyl group, 3- Examples thereof include a sulfopropyl group and a 4-sulfobutyl group. Examples of the substituent of the substituted alkyl group include hydroxyl group; alkoxy group such as methoxy group and ethoxy group; cyano group; halogen atom such as fluorine atom, chlorine atom, bromine atom and iodine atom; carboxylate salt and sulfonic acid Examples thereof include ionic hydrophilic groups such as salts.

  In the general formula (1), the substituted or unsubstituted aryl group is preferably an aryl group having 6 to 12 carbon atoms. However, in the case of a substituted aryl group, the number of carbon atoms does not include the number of carbon atoms of the substituent. Examples of the substituted or unsubstituted aryl group include phenyl group, naphthyl group, p-tolyl group, p-octylphenyl group, mesityl group, p-methoxyphenyl group, o-chlorophenyl group, m- (3-sulfo group). Propylamino) phenyl group and the like. Examples of the substituent of the substituted aryl group include an alkyl group such as a methyl group, an ethyl group, an isopropyl group, a tert-butyl group, and an n-octyl group; an alkoxy group similar to the above; a halogen atom similar to the above; Alkylamino groups such as amino and dimethylamino groups; amide groups; carbamoyl groups; sulfamoyl groups; sulfoamide groups; hydroxyl groups; ester groups such as methoxycarbonyl groups and ethoxycarbonyl groups; It is done.

  In the general formula (1), the substituted or unsubstituted heterocyclic group is preferably a 5-membered or 6-membered heterocyclic group. Examples of the substituted or unsubstituted heterocyclic group include 2-pyridyl group, 2-thienyl group, 2-thiazolyl group, 2-benzothiazolyl group, 2-furyl group, 6-sulfobenzothiazolyl group, 6 -A sulfonate benzothiazolyl group and the like. Examples of the substituent of the substituted heterocyclic group include an amide group; a carbamoyl group; a sulfamoyl group; a sulfoamide group; a hydroxyl group; an ester group as described above; and an ionic hydrophilic group as described above.

  In the general formula (1), examples of the substituted or unsubstituted sulfonyl group include a methylsulfonyl group and a phenylsulfonyl group. Examples of the substituent of the substituted sulfonyl group include a substituted or unsubstituted alkyl group similar to the above, a substituted or unsubstituted aryl group similar to the above.

  In the general formula (1), the substituted or unsubstituted acyl group is preferably an acyl group having 1 to 12 carbon atoms. However, in the case of a substituted acyl group, the number of carbon atoms does not include the number of carbon atoms of the substituent. Examples of the substituted or unsubstituted acyl group include an acetyl group, a benzoyl group, and a chloroacetyl group. Examples of the substituent of the substituted acyl group include the same ionic hydrophilic groups as described above.

In the general formula (1), as described above, A ₁ and A ₂ are both substituted or unsubstituted carbon atoms, or one is a substituted or unsubstituted carbon atom and the other is nitrogen. Is an atom. The case where both A ₁ and A ₂ are carbon atoms is preferable in that it can exhibit more excellent performance. Examples of the substituent bonded to a carbon atom of A ₁ and A _2, for example, an alkyl group having 1 to 3 carbon atoms, a carboxyl group, a carbamoyl group, a cyano group, and the like.

As described above, in the general formula (1), R ₄ and R ₅ are not both hydrogen atoms, and R ₆ and R ₇ are not both hydrogen atoms. Moreover, in the said General formula (1), when the substitution number of a sulfonic acid group or a carboxyl group increases, there exists a tendency for the water solubility of the said dye to improve, Therefore It is preferable to adjust those substitution numbers as needed.

As a preferable embodiment of the dye, for example, in the general formula (1), R ₁ is an alkyl group, R ₂ is a cyano group, R ₃ is a hydrogen atom or a substituted or unsubstituted heterocyclic group, and R ₄ is a hydrogen atom. , A substituted or unsubstituted heterocyclic group or substituted aryl group, R ₅ and R ₆ are each a substituted heterocyclic group or substituted aryl group, R ₇ is a hydrogen atom, and A ₁ is a substituted carbon atom, An embodiment in which A ₂ is a substituted or unsubstituted carbon atom is exemplified.

As a more preferable embodiment of the dye, for example, in the general formula (1), R ₁ is substituted with a tert-butyl group, R ₂ is a cyano group, R ₃ is substituted with a hydrogen atom or a sulfonic acid group or an alkali metal base thereof. A benzothiazolyl group (preferably benzothiazol-2-yl group), R ₄ may be substituted with a hydrogen atom, a sulfonic acid group or an alkali metal base thereof (preferably benzothiazol-2-yl) Group) or a trialkylphenyl group (preferably a mesityl group) substituted with a sulfonic acid group or an alkali metal base thereof, and R ₅ and R ₆ are each substituted with a sulfonic acid group or an alkali metal base thereof. A good mono, di or trialkylphenyl group (preferably a p-octylphenyl group) Is a benzothiazolyl group (preferably substituted with properly the mesityl) or a sulfonic acid group or alkali metal bases, benzothiazol-2-yl group), R ₇ is a hydrogen atom, A ₁ is an alkyl group (preferably is an aspect of carbon atoms which is substituted, a ₂ is a carbon atoms which may be substituted with a cyano group with a methyl group).

  Preferable specific examples of the dye include compounds represented by the following chemical formulas (1-A) to (1-F).

In the compound represented by the chemical formula (1-A), in the general formula (1), R ₁ is a tert-butyl group, R ₂ is a cyano group, R ₃ is a benzothiazol-2-yl group, and R ₄ is A hydrogen atom, R ₅ and R ₆ are p-octylphenyl groups, R ₇ is a hydrogen atom, A ₁ is a carbon atom substituted with a methyl group, and A ₂ is a carbon atom substituted with a cyano group It is an aspect.

In the compound represented by the chemical formula (1-B), in the general formula (1), R ₁ is a tert-butyl group, R ₂ is a cyano group, R ₃ and R ₄ are benzothiazol-2-yl groups, In this embodiment, R ₅ and R ₆ are mesityl groups, R ₇ is a hydrogen atom, A ₁ is a carbon atom substituted with a methyl group, and A ₂ is a carbon atom.

The compound represented by the chemical formula (1-C) is the compound represented by the general formula (1) in which R ₁ is a tert-butyl group, R ₂ is a cyano group, R ₃ and R ₄ are 6-sulfosodium salt benzothiazole- A mode in which 2-yl group, R ₅ and R ₆ are 3-sulfosodium salt-mesityl group, R ₇ is a hydrogen atom, A ₁ is a carbon atom substituted with a methyl group, and A ₂ is a carbon atom is there.

In the compound represented by the chemical formula (1-D), in the general formula (1), R ₁ is a tert-butyl group, R ₂ is a cyano group, R ₃ and R ₄ are 6-sulfolithium salt benzothiazole- A carbon atom in which a 2-yl group, R ₅ and R ₆ are 2,6-diethyl-4-methyl-3-sulfolithium phenyl group, R ₇ is a hydrogen atom, and A ₁ is substituted with a methyl group, In this embodiment, A ₂ is a carbon atom.

In the compound represented by the chemical formula (1-E), in the general formula (1), R ₁ is a tert-butyl group, R ₂ is a cyano group, R ₃ and R ₄ are 6-sulfo potassium salt benzothiazole- A mode in which 2-yl group, R ₅ and R ₆ are 3-sulfo potassium salt-mesityl group, R ₇ is a hydrogen atom, A ₁ is a carbon atom substituted with a methyl group, and A ₂ is a carbon atom is there.

The compound represented by the chemical formula (1-F) is the compound represented by the general formula (1), in which R ₁ is a tert-butyl group, R ₂ is a cyano group, R ₃ and R ₄ are 6-sulfolithium benzothiazole- 2-yl group, R ₅ and R ₆ are 2,6-diethyl-4-sulfolithium phenyl groups, R ₇ is a hydrogen atom, A ₁ is a carbon atom substituted with a methyl group, and A ₂ is carbon This is an embodiment that is an atom.

  As described above, the blending amount of the dye is 0.1 to 1.0% by weight (the condition of 0.1 ≦ x ≦ 1.0 is satisfied). By making the blending amount of the dye within the above range, an ink excellent in print quality can be obtained, and, for example, a light color can be expressed without reducing the dot density, thereby generating a grainy feeling. And can be suitably used as light ink.

  The colorant may be composed of only the dye, or may further contain other dyes, pigments, and the like as long as the effects of the present invention are not impaired.

  The water is preferably ion exchange water or pure water. The blending amount of water with respect to the total amount of the ink is, for example, 10 to 90% by weight, and preferably 40 to 80% by weight. The blending amount of water may be, for example, the balance of other components.

  The water-soluble organic solvent is classified into, for example, a wetting agent that prevents the ink from drying at the tip of the ink jet head and a penetrating agent that adjusts the drying speed on the surface of the recording paper.

  The wetting agent is not limited, and examples thereof include lower alcohols such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol; dimethylformamide, dimethylacetamide, and the like. Amides; ketones such as acetone; keto alcohols such as diacetone alcohol; ethers such as tetrahydrofuran and dioxane; polyhydric alcohols such as polyalkylene glycol, alkylene glycol, and glycerin; 2-pyrrolidone; N-methyl-2-pyrrolidone; , 3-dimethyl-2-imidazolidinone and the like. The polyalkylene glycol is not limited, and examples thereof include polyethylene glycol and polypropylene glycol. The alkylene glycol is not limited, and examples thereof include ethylene glycol, propylene glycol, butylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, thiodiglycol, and hexylene glycol. Among these, polyhydric alcohols such as alkylene glycol and glycerin are preferable. These wetting agents may be used alone or in combination of two or more.

  The blending amount of the wetting agent is not particularly limited. The blending amount of the wetting agent with respect to the total amount of the ink is, for example, 0 to 95% by weight, preferably 10 to 80% by weight, and more preferably 10 to 50% by weight.

  The inkjet recording ink of the present invention contains dipropylene glycol propyl ether (DPP) as the penetrant. As described above, the blending amount of the DPP is 0.5 to 3.0% by weight (the condition of 0.5 ≦ y ≦ 3.0 is satisfied) with respect to the total amount of the ink.

  The penetrant may be composed only of the DPP, or may further contain other penetrants as long as the effects of the present invention are not impaired.

  The penetrant other than the DPP is not limited, for example, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol propyl ether, diethylene glycol methyl ether, diethylene glycol ethyl ether, diethylene glycol propyl ether, diethylene glycol butyl ether, triethylene glycol methyl ether, Triethylene glycol ethyl ether, triethylene glycol propyl ether, triethylene glycol butyl ether, propylene glycol methyl ether, propylene glycol ethyl ether, propylene glycol propyl ether, propylene glycol butyl ether, dipropylene glycol methyl ether, dipropylene glycol ethyl ether Le, dipropylene glycol butyl ether, tripropylene glycol methyl ether, tripropylene glycol ethyl ether, tripropylene glycol propyl ether, tripropylene glycol butyl ether. One type of penetrant other than the DPP may be used, or two or more types may be used.

As described above, the ink of the present invention contains an acetylene glycol surfactant. The acetylene glycol surfactant includes the surfactant represented by the general formula (2). In the general formula (2), m and n may be the same or different, and are numbers satisfying m + n = 1 to 15, preferably m + n = 3 to 11. R ₁₁ , R ₁₂ , R ₁₃ and R ₁₄ may be the same or different, and are each a linear or branched alkyl group having 1 to 5 carbon atoms. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, and a butyl group.

  As the surfactant represented by the general formula (2), for example, a commercially available product may be used. Examples of the commercially available products include Olfin (registered trademark) E1010, Olphine (registered trademark) E1004, Surfynol (registered trademark) 440 and Surfinol (registered trademark) 465 manufactured by Nissin Chemical Industry Co., Ltd .; Examples thereof include acetylenol (registered trademark) E40 and acetylenol (registered trademark) E100 manufactured by KK.

  As described above, the surfactant represented by the general formula (2) is blended so as to satisfy the condition (C).

  The ink for inkjet recording of the present invention may contain a surfactant other than the surfactant represented by the general formula (2) as long as the effects of the present invention are not impaired. The surfactant other than the surfactant represented by the general formula (2) is not limited, and examples thereof include an anionic surfactant “EMAL (registered trademark)” series and “LATEMUL (registered trademark)” manufactured by Kao Corporation. ) ”Series,“ VENOL (registered trademark) ”series,“ NEOPELEX (registered trademark) ”series, NS SOAP, KS SOAP, OS SOAP,“ PELEX (registered trademark) ”series, etc .; manufactured by Lion Corporation Agents “LIPOLAN (registered trademark)” series, “LIPON (registered trademark)” series, “Sunnol (registered trademark)” series, “LIPOTAC (registered trademark)” series, “ENAGICOL (registered trademark)” series, “LIPAL (registered trademark)” Trademark) ”series,“ LOTAT (registered trademark) ”series, etc .; manufactured by Kao Corporation On-surfactant “EMULGEN (registered trademark)” series, “RHEODOL (registered trademark)” series, “EMASOL (registered trademark)” series, “EXCEL (registered trademark)” series, “EMANON (registered trademark)” series, “ "AMIET (registered trademark)" series, "AMINON (registered trademark)" series, etc .; Nonionic surfactant "DOBANOX (registered trademark)" series, "LEOCOL (registered trademark)" series, "LEOX (registered trademark)" manufactured by Lion Corporation Trademark) series, “LAOL (registered trademark)” series, “LEOCON (registered trademark)” series, “LIONOL (registered trademark)” series, “CADENAX (registered trademark)” series, “LIONON (registered trademark)” series, "LEOFAT (registered trademark)" series etc. That. One type of surfactant other than the surfactant represented by the general formula (2) may be used, or two or more types may be used.

  The ink may further contain a conventionally known additive as required. Examples of the additive include a viscosity adjusting agent, a surface tension adjusting agent, and an antifungal agent. The viscosity modifier is not limited, and examples thereof include polyvinyl alcohol, cellulose, and a water-soluble resin.

  The ink is, for example, a colorant, water, a water-soluble organic solvent, and an acetylene glycol surfactant and, if necessary, other additive components uniformly mixed by a conventionally known method, and is insoluble by a filter. Can be prepared by removing.

  As described above, the ink of the present invention is formulated so that the dye, the dipropylene glycol propyl ether, and the surfactant represented by the general formula (2) satisfy the conditions (A) to (C). Therefore, it is excellent in ejection stability and printing quality, and also prevents the compound derived from a rubber member or the like in the ink jet recording apparatus from being eluted into the ink.

  As described above, the ink of the present invention can be used as, for example, a magenta ink. However, the present invention is not limited to this. The ink of the present invention can be made into an ink of a color other than magenta by using a colorant other than the dye.

  The ink cartridge of the present invention is an ink cartridge containing the ink for inkjet recording of the present invention. As the main body of the ink cartridge of the present invention, for example, a conventionally known one can be used.

  Next, the ink jet recording apparatus of the present invention will be described. The ink jet recording apparatus of the present invention includes the ink cartridge of the present invention. Except for this, the configuration of the ink jet recording apparatus of the present invention may be the same as that of a conventionally known ink jet recording apparatus, for example.

  FIG. 2 shows a configuration of an example of the ink jet recording apparatus of the present invention. As shown in the figure, the ink jet recording apparatus 1 includes four ink cartridges 2, an ink jet head 3, a head unit 4, a carriage 5, a drive unit 6, a platen roller 7, and a purge device 8. Including as a member.

  The four ink cartridges 2 contain one color each of four colors of yellow, magenta, cyan, and black. For example, the magenta ink is the ink of the present invention. The ink jet head 3 performs printing on a recording material P such as recording paper. The head unit 4 includes the inkjet head 3. The four ink cartridges 2 and the head unit 4 are mounted on the carriage 5. The drive unit 6 reciprocates the carriage 5 in a linear direction. The platen roller 7 extends in the reciprocating direction of the carriage 5 and is disposed to face the ink jet head 3.

  The drive unit 6 includes a carriage shaft 9, a guide plate 10, two pulleys 11 and 12, and an endless belt 13. The carriage shaft 9 is disposed at the lower end of the carriage 5 and extends in parallel with the platen roller 7. The guide plate 10 is disposed at the upper end of the carriage unit 5 and extends in parallel with the carriage shaft 9. The two pulleys 11 and 12 are disposed between the carriage shaft 9 and the guide plate 10 at both ends of the carriage shaft 9. The endless belt 13 is stretched between the two pulleys 11 and 12.

  In the ink jet recording apparatus 1, when the pulley 11 is rotated forward and backward by driving the carriage motor 101, the carriage 5 joined to the endless belt 13 is moved along with the forward and reverse rotation of the pulley 11. Along the carriage shaft 9 and the guide plate 10, it reciprocates in a linear direction.

  The recording material P is fed from a paper feed cassette (not shown) provided on the side or lower side of the ink jet recording apparatus 1. The recording material P is introduced between the inkjet head 3 and the platen roller 7. Then, predetermined printing is performed on the recording material P by the ink ejected from the inkjet head 3. Thereafter, the recording material P is discharged from the ink jet recording apparatus 1. In FIG. 2, the paper feed mechanism and paper discharge mechanism for the recording material P are not shown.

  The purge device 8 is provided on the side of the platen roller 7 so as to face the inkjet head 3 when the head unit 4 is at a reset position (in this example, the upper portion of the purge device 8). Has been placed. The purge device 8 includes a purge cap 14, a pump 15 and a cam 16, and an ink storage unit 17. The purge cap 14 covers a plurality of nozzles (not shown) of the inkjet head 3 when the head unit 4 is in the reset position. The pump 15 sucks out defective ink containing bubbles and the like accumulated in the ink jet head 3 by driving the cam 16. Thereby, recovery of the inkjet head is achieved. The sucked defective ink is stored in the ink storage unit 17.

  A wiper member 20 is disposed adjacent to the purge device 8 at a position on the platen roller 7 side of the purge device 8. The wiper member 20 is formed in a spatula shape, and wipes the nozzle forming surface of the inkjet head 3 as the carriage 5 moves. In FIG. 2, a cap 18 covers a plurality of nozzles of the inkjet head 3 that are returned to the reset position when printing is completed in order to prevent ink from drying.

  In the ink jet recording apparatus 1 of this example, the four ink cartridges 2 are mounted on one carriage 5. However, the present invention is not limited to this. In the ink jet recording apparatus of the present invention, the four ink cartridges may be mounted on a plurality of carriages. Further, the ink cartridge may not be mounted on the carriage but may be arranged and fixed in the ink jet recording apparatus. In this aspect, for example, the ink cartridge and the head unit mounted on the carriage are connected by a tube or the like, and the ink is supplied from the ink cartridge to the head unit by the tube or the like.

  Next, examples of the present invention will be described together with comparative examples. The present invention is not limited or restricted by the following examples and comparative examples.

[Examples 1-12 and Comparative Examples 1-15]
The ink composition components (Tables 1 and 2 below) were mixed uniformly. Thereafter, the obtained mixture was filtered using a hydrophilic polytetrafluoroethylene (PTFE) type membrane filter (pore diameter 0.2 μm) manufactured by Toyo Roshi Kaisha, Ltd., so that Examples 1 to 12 and Comparative Example 1 were used. ˜15 ink jet recording inks were obtained. In Tables 1 and 2, dyes (1-A) to (1-F) are compounds represented by the chemical formulas (1-A) to (1-F), respectively.

  For the inks of the examples and comparative examples, (a) print quality evaluation (bleeding), (b) print quality evaluation (feathering), (c) jetting stability evaluation, (d) ozone resistance evaluation, (e ) Light resistance evaluation, (f) Rubber precipitation evaluation, and (g) Comprehensive evaluation were performed by the following methods. Samples for (d) ozone resistance evaluation and (e) light resistance evaluation were prepared as follows.

That is, first, the ink cartridges were filled with the inks of the examples and the comparative examples. Subsequently, the ink cartridge was mounted on a digital multifunction device DCP-330C equipped with an inkjet printer manufactured by Brother Industries, Ltd. Next, the ink gradation sample was printed on photographic glossy paper BP61GLA manufactured by Brother Industries, Ltd. to obtain a patch with an initial OD value of 0.8. The OD value was measured with a spectrocolorimeter Spectrolino (light source: D ₆₅ ; field of view: 2 °; status A) manufactured by Gretag Macbeth.

(A) Print quality evaluation (bleeding)
Using a digital multifunction printer DCP-330C equipped with an inkjet printer manufactured by Brother Industries, Ltd., on the office paper W manufactured by Fujitsu Cower Co., Ltd. The evaluation sample was printed using the black ink filled in the ink cartridge LC10BK manufactured by Co., Ltd. The Rag at the boundary between the ink of each example and each comparative example and the black ink was measured by a method according to ISO 13660. Here, “Rag” is a line radiance defined by ISO 13660, and a “rugget line” indicates a state of undulation with respect to an ideal line edge that should be smooth and straight. The obtained Rag was evaluated according to the following evaluation criteria.

Print quality evaluation (bleeding) criteria A: Line Rag is less than 30 C: Line Rag is 30 or more

(B) Print quality evaluation (feathering)
Using a digital multifunction printer DCP-330C equipped with an inkjet printer manufactured by Brother Industries, Ltd., text printing was performed on office paper W manufactured by Fujitsu Coalco using the inks of the respective examples and comparative examples. . The result of the text printing was evaluated according to the following evaluation criteria. Feathering is a fine ink permeation blur that occurs on the paper surface due to the presence of fibers and voids in the recording material.

Print quality evaluation (feathering) standard A: Feathering was not recognized, and the edges of the text were sharp.
C: Feathering was slightly noticeable, or obviously feathering was noticeable, and the edges of the text were not sharp.

(C) Evaluation of jetting stability Using the digital printer DCP-330C equipped with an inkjet printer manufactured by Brother Industries, Ltd., on office paper W manufactured by Fujitsu Cower Co., Ltd., 100 million dots (approximately 30,000 sheets) Continuous printing was performed. The results of the continuous printing were evaluated according to the following criteria. Non-ejection is a state in which the nozzles of the inkjet head are clogged and the ink is not ejected. The ejection bend is a state in which a part of the nozzles of the inkjet head is clogged and the ink is ejected obliquely without being ejected perpendicularly to the recording paper.

Ejection stability evaluation criteria A: During continuous printing, there was no non-ejection and ejection bend, or there was no non-ejection or ejection bend, but the non-ejection or ejection bend was recovered by purging within 5 times. did.
C: During continuous printing, there were many non-ejections and ejection bends, and both the non-ejections and ejection bends were not recovered after 5 purges.

(D) Ozone resistance evaluation Using the ozone weather meter OMS-H manufactured by Suga Test Instruments Co., Ltd., the gradation sample was measured under the conditions of an ozone concentration of 2 ppm, a bath temperature of 24 ° C, and a bath relative humidity of 60%. Left for hours. Subsequently, the OD value of the patch after the standing was measured in the same manner as described above. Next, the OD value reduction rate (%) was obtained by the following formula (I), and the ozone resistance was evaluated according to the following evaluation criteria. Note that the smaller the OD value reduction rate, the less the deterioration of image quality and the better the ozone resistance.

OD value decrease rate (%) = {(XY) / X} × 100 (I)
X: 0.8 (initial OD value)
Y: OD value after standing

Ozone resistance evaluation standard A: OD value reduction rate is less than 20% C: OD value reduction rate is 20% or more

(E) Light resistance evaluation Using the high energy xenon weather meter SC750-WN manufactured by Suga Test Instruments Co., Ltd., the gradation sample was subjected to xenon under the conditions of a bath temperature of 25 ° C., a bath relative humidity of 50%, and an illuminance of 93 klx. Lamp light was irradiated for 200 hours. Subsequently, the OD value of the patch after the irradiation was measured in the same manner as described above. Next, the OD value reduction rate (%) was determined by the following formula (II), and the light resistance was evaluated according to the following evaluation criteria. Note that the smaller the OD value reduction rate, the less the image quality is deteriorated and the better the light resistance.

OD value reduction rate (%) = {(XY) / X} × 100 (II)
X: 0.8 (initial OD value)
Y: OD value after irradiation

Light resistance evaluation standard A: OD value reduction rate is less than 30% C: OD value reduction rate is 30% or more

(F) Rubber precipitation evaluation Under the condition that the contact area per 1 g of ink is 30 mm ² , a rubber piece (ethylene propylene rubber (EPDM); rubber hardness (measured by old JIS K 6301 A type) 40 °) is applied to the ink. It was immersed and stored in an environment at a temperature of 70 ° C. for 1 week. After the storage, the rubber piece was taken out from the ink, and then the ink was filtered through a hydrophilic polytetrafluoroethylene (PTFE) type membrane filter (pore diameter: 0.2 μm; diameter: 15 mm) manufactured by Toyo Roshi Kaisha, Ltd. The time required for filtration was measured. As a control, the ink before storage was filtered under the same conditions as described above, and the time required for filtration was measured. Next, the increase rate of filtration time was calculated | required by following formula (III), and rubber | gum precipitation nature was evaluated in accordance with the following evaluation criteria.

Increase rate of filtration time = Y / X (III)
X: Filtration time before storage Y: Filtration time after storage

Rubber precipitation evaluation criteria A: Filtration time increase rate is less than 1.3 times C: Filtration time increase rate is 1.3 times or more

(G) Comprehensive evaluation From the results of the above (a) to (f), comprehensive evaluation was performed for each ink according to the following evaluation criteria.

Overall evaluation criteria A: All evaluation results were A.
C: C was found in any of the evaluation results.

  The composition and evaluation results of the inks of each example are shown in Table 1 below. The composition and evaluation results of the inks of the comparative examples are shown in Table 2 below.

  As shown in Table 1, the inks of Examples 1 to 12 were evaluated for printing quality evaluation (bleeding), printing quality evaluation (feathering), jetting stability evaluation, ozone resistance evaluation, light resistance evaluation, and rubber deposition evaluation. All results were good. On the other hand, as shown in Table 2, the inks of Comparative Examples 1, 3, and 5 not containing the surfactant represented by the general formula (2) had inferior print quality evaluation (bleeding) results. Further, the amount of the surfactant represented by the general formula (2) is large relative to the amount of the dye and DPP, and the inks of Comparative Examples 2 and 6 that do not satisfy the condition (C) have the print quality. The result of evaluation (feathering) was inferior. Further, the amount of the surfactant represented by the general formula (2) is large relative to the amount of the dye and DPP, and the ink of Comparative Example 4 that does not satisfy the condition (C) has a print quality evaluation ( The result of feathering was inferior. Further, the ink of Comparative Example 7 in which the blending amount of the surfactant represented by the general formula (2) is small relative to the blending amount of the dye and DPP, and the ink of Comparative Example 7 that does not satisfy the condition (C) is evaluated for printing quality ( Bleeding) was inferior. Further, the amount of the surfactant represented by the general formula (2) is large relative to the amount of the dye and DPP, and the ink of Comparative Example 8 that does not satisfy the condition (C) has a print quality evaluation ( The result of feathering was inferior. Further, the ink of Comparative Example 9 where y> 3.0 was inferior in the jetting stability evaluation result. Further, the ink of Comparative Example 10 containing no DPP was inferior in the print quality evaluation (bleeding) result. Further, the ink of Comparative Example 11 containing no DPP was inferior in print quality evaluation (bleeding) due to dipropylene glycol methyl ether blended in place of DPP. Further, the inks of Comparative Examples 12 and 13 not containing DPP had inferior print quality evaluation (feathering) and rubber deposition evaluation results due to dipropylene glycol butyl ether or propylene glycol propyl ether blended in place of DPP. . Further, in place of the dye (1), C.I. I. Acid Red 14 or C.I. I. The inks of Comparative Examples 14 and 15 using Direct Red 227 were inferior in the results of ozone resistance evaluation and light resistance evaluation.

  As described above, the ink of the present invention is excellent in ejection stability and print quality, prevents elution of a compound derived from a rubber member or the like in an ink jet recording apparatus into the ink, and improves the fastness of a recorded matter. Is also excellent. The use of the ink of the present invention is not limited and can be widely applied to various ink jet recordings.

FIG. 1 shows the amount (x) of the dye, the amount (y) of dipropylene glycol propyl ether (DPP), and the surfactant represented by the general formula (2) in the inkjet recording ink of the present invention. It is a figure for demonstrating quantity (z). FIG. 2 is a schematic perspective view showing an example of the configuration of the ink jet recording apparatus of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inkjet recording device 2 Ink cartridge 3 Inkjet head 4 Head unit 5 Carriage 6 Drive unit 7 Platen roller 8 Purge device 9 Carriage shaft 10 Guide plate

Claims (5)

An ink for ink jet recording comprising a colorant, water, a water-soluble organic solvent, and an acetylene glycol surfactant,
The colorant contains a dye represented by the following general formula (1),
The water-soluble organic solvent comprises dipropylene glycol propyl ether;
The acetylene glycol-based surfactant includes a surfactant represented by the following general formula (2),
The dye, the dipropylene glycol propyl ether, and the surfactant represented by the general formula (2) are blended so as to satisfy the following conditions (A) to (C), respectively. Ink for ink jet recording.

(A) 0.1 ≦ x ≦ 1.0
(B) 0.5 ≦ y ≦ 3
(C) In y ≧ 25x / 9 + 2/9,
−175x + 18y + 225z−104 ≦ 0 and
−100x + 18y + 225z−66.5 ≧ 0
In y ≦ 25x / 9 + 2/9,
−275x + 54y + 225z−112 ≦ 0 and
−200x + 54y + 225z−74.5 ≧ 0
x: blending amount (% by weight) of the dye with respect to the total amount of the ink
y: blending amount of dipropylene glycol propyl ether with respect to the total amount of ink (% by weight)
z: blending amount (wt%) of the surfactant represented by the general formula (2) with respect to the total amount of ink

In the general formula (1),
R ₁ is a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group,
R ₂ is a hydrogen atom, a halogen atom or a cyano group,
R ₃ is a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group,
R ₄ , R ₅ , R ₆ and R ₇ are each a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted sulfonyl group A substituted or unsubstituted acyl group, and R ₄ , R ₅ , R ₆ and R ₇ may be the same or different, but R ₄ and R ₅ are not both hydrogen atoms, and R ₆ and R ₇ is not both a hydrogen atom,
A ₁ and A ₂ are both substituted or unsubstituted carbon atoms, or one is a substituted or unsubstituted carbon atom and the other is a nitrogen atom.

In the general formula (2), m and n may be the same or different, and are numbers satisfying m + n = 1 to 15,
R ₁₁ , R ₁₂ , R ₁₃ and R ₁₄ may be the same or different, and are each a linear or branched alkyl group having 1 to 5 carbon atoms. The ink for inkjet recording according to claim 1, which is used as a light ink. The ink for inkjet recording according to claim 1 or 2, which is used as a magenta ink. An ink cartridge comprising an ink jet recording ink, wherein the ink is the ink jet recording ink according to any one of claims 1 to 3. An ink jet recording apparatus comprising an ink cartridge and ink ejecting means, wherein ink for ink jet recording is ejected from the ink ejecting means, wherein the ink cartridge is the ink cartridge according to claim 4. apparatus.

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